JPH089446A - Cordless phone - Google Patents

Abstract

(57) [Abstract] [Purpose] To reliably establish a call connection between the master and the slave, and to extend the maximum standby time of the slave by the secondary battery without delaying the reaction time to the master. A noise level is detected at a frequency at which the first control channel is located in the reception frequency of the reception circuit unit 13, and a reception frequency in the reception circuit unit 13 is set to a second level.
The noise level is detected at the frequency where the control channel is located, and which level is lower is determined. Then, the master unit control unit 18 controls the transmission circuit unit 12 to transmit the control signal thereafter using only the control channel determined to have the low level, and transmits the control signal to the slave unit 2, Machine 1 communicates that it will subsequently use this control channel. Then, the handset unit 2 receives the control signal by the receiving circuit section 24 and extracts the control signal, and the handset unit control section 28 recognizes the control channel used by the base unit 1 thereafter based on the control signal, and thereafter controls the control channel. The receiving circuit unit 24 is controlled so that the intermittent reception is performed only for the channels.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-access channel type cordless telephone.

[0002]

2. Description of the Related Art Conventionally, in a cordless telephone, a base unit which is a radio base station connected to a general subscriber telephone line and a handset unit which is a mobile station connected to the base unit through a plurality of radio channels are provided. Equipped with, select an empty channel from a plurality of wireless channels, send the data related to the channel via the control channel, and the communication channel with the base unit based on the data related to the empty channel included in the control channel on the handset side. There is a so-called multi-access channel method in which a call is connected to the base unit when the handset is in standby mode by recognizing that the cordless handset has such a multi-access channel type wireless connection with the handset. Two control channels for controlling are set over different frequencies.

As such a multi-access channel type cordless telephone, one which controls wireless connection between a master unit and a slave unit by using only one control channel among two control channels and two control channels In some cases, the wireless connection control between the master unit and the slave unit is performed using both of them.

In such a multi-access channel type cordless telephone, as in the former case, one of the two control channels is used to control the wireless connection between the master unit and the slave unit. Either one of the two control channels is written in the storage means configured by the E ² PROM or the like provided in the master unit and the slave unit at the time of factory shipment, and the memory of the master unit and the slave unit is stored in subsequent use. The wireless connection control between the master unit and the slave unit is performed using the control channel stored in the means.

In the latter case, in which both the two control channels are used to establish a wireless connection between the master unit and the slave unit, an E ² PROM provided in the master unit and the slave unit is used. Write two control channels to the storage means,
In addition, in the master unit, the two control channels stored in the storage means can be selectively switched by a manual operation, and during subsequent use, the control channel may affect the television or from other electric products depending on the installation state of the master unit. Since it is affected by the generated electromagnetic waves, the control channel used for the wireless connection control between the master unit and the slave unit was switched by a manual operation so as not to have these effects.

Further, as in the latter case in which both of the two control channels are used to establish a wireless connection between the master unit and the slave unit, as disclosed in Japanese Patent Laid-Open No. 17734/1990,
Two control channels are written in the storage means provided in the master unit and the slave unit, and when used thereafter, the call connection between the master unit and the slave unit during standby of the slave unit is performed by using a plurality of wireless channels of the master unit. A vacant channel is selected from the inside, and the data relating to the channel is sent out through one of the control channels stored in the storage means. on the other hand,
The slave unit alternately receives two control channels, and when the received control channel includes data about an empty channel, by recognizing the communication channel with the master unit based on the data about the empty channel, The call was connected to the base unit when the handset was on standby.

[0007]

By the way, in the cordless telephone such as the above-mentioned conventional device, the slave unit is usually driven by the secondary battery, and therefore, the continuous control is performed to extend the maximum standby time of the slave unit by the battery. Instead of holding the reception state of the channel, the control channel is intermittently received.

Therefore, in the conventional device which controls the wireless connection between the master unit and the slave unit by using only one control channel among the two control channels as in the former case, the slave unit receives one control channel. Therefore, it is possible to easily extend the maximum standby time of the slave by setting a large intermittent reception timing, and the slave does not delay the reaction to the signal from the master so much.
However, even if the control channel is affected by electromagnetic waves emitted from other electric appliances depending on the installation state of the parent device, the control channel cannot be switched,
There is a problem that the wireless connection control and the call connection between the master unit and the slave unit cannot be performed.

Further, in the conventional device which controls the wireless connection between the master unit and the slave unit by using both of the two control channels like the latter, two control channels are used for the wireless connection between the master unit and the slave unit. When selecting either control channel by manual operation to select a control channel with less influence based on the installation state of the base unit, or when transmitting data related to an empty channel via the control channel, 2 By selecting and transmitting one of the two control channels, it is possible to select the control channel that is not affected by the electromagnetic waves emitted from other electric appliances, thus solving the problem of the former conventional device. Although it is possible, the slave unit must receive two control channels, and the two control channels are received alternately. Since you are, and you Nobaso between maximum handset standby time by a large timing of the intermittent reception, there is a problem that the response to signals from the base unit is delayed at the slave unit.

According to the present invention, the wireless connection control and the call connection between the master unit and the slave unit can be surely performed, and the maximum standby time of the slave unit can be maintained without delaying the reaction to the master unit. It is intended to provide a cordless telephone that can be extended.

[0011]

In order to achieve the above object, the invention as set forth in claim 1 includes a master unit connected to a telephone line, and a slave unit connected to the master unit by a plurality of wireless channels. The parent device comprises a control channel selecting means for selecting a control channel used for connection control with the child device from two preset control channels, and a call channel selecting for selecting an empty channel from a plurality of wireless channels. Means and control signal transmitting means for transmitting data relating to the vacant channel selected by the call channel selecting means via the control channel selected by the control channel selecting means, while the slave unit is the master unit. Signal receiving means for intermittently receiving two control channels preset in the machine, and the control signal receiving means Therefore, a communication channel recognition means for recognizing a communication channel used for a communication with the master device based on the received data about the empty channel included in the control channel is provided, and the master device and the slave device at the standby time of the slave device. In the cordless telephone, the cordless telephone is connected to the cordless handset by receiving data regarding an empty channel selected in the parent device through the control channel. In the parent device, two preset control channels are set. Interference detection means for respectively detecting the interference, a determination means for determining which control channel has less interference based on a detection signal from the interference detection means, and the determination means determines that the interference is less. Control channel so that only the control channel selected by the control channel selection means is selected. A master unit control means for transmitting the determination result by the master unit through the control channel, and the slave unit controls the master unit to select based on the determination result included in the control channel received by the control signal receiving unit. A slave unit control means for controlling only the channel so that the control signal receiving means intermittently receives is provided.

According to a second aspect of the present invention, there is provided manual operation means for arbitrarily controlling the control channel selection means by the master device control means, and the master device control means responds to the operation by the manual operation device. Then, the control channel selecting means temporarily releases the already selected state, and again controls the channel selecting means to select only the control channel which is judged to be less disturbed by the judging means. The determination result is transmitted via the previously selected control channel.

According to a third aspect of the present invention, the interference detection means and the determination means always detect the interference applied to the two preset control channels to determine which control channel has less interference. When the control channel determined to be less disturbed by the disturbance detection means and the determination means is different from the previously selected control channel, the master unit control means only controls the control channel determined to be less disturbed by the determination means. The channel selection means controls the selection, and the determination result of the determination means is transmitted through the previously selected control channel.

[0014]

Therefore, according to the first aspect of the present invention, in the base unit, the interference detection means detects the interference applied to the two preset control channels, and which of the determination means is based on the detection signal. It is determined whether the control channel has less interference, and the master unit control unit controls the control channel selection unit to select only the control channel determined to have less interference, and the determination result by the determination unit is transmitted to the slave unit. Send. Then, in the slave, when the control signal receiving means receives the control channel, the slave signal controlling means causes the control signal receiving means to select only the control channel selected by the master based on the determination result included in the received control channel. By controlling to receive intermittently, as a call connection between the master unit and the slave unit during standby of the slave unit, a control channel that is not affected by electromagnetic waves emitted from other electric products is selected in advance, It is performed by the one control channel.

According to the second aspect of the invention, in response to the operation by the manual operation means, the master unit control means temporarily cancels the already selected state by the control channel selection means, and along with the cancellation, the interference detection means. Detects interference on two preset control channels, and the determination unit determines which control channel has less interference based on the detection signal, and the master unit control unit determines that there is less interference. The control channel selection means again controls only the selected control channel, and the determination result by the determination means is transmitted to the slave unit through the previously selected control channel. Then, in the slave, when the control signal receiving means receives the control channel, the slave signal controlling means causes the control signal receiving means to select only the control channel selected by the master based on the determination result included in the received control channel. By controlling so as to receive intermittently, it is possible to re-set a good control channel that is not affected by electromagnetic waves emitted from other electric appliances by the user's operation.

According to the third aspect of the invention, the interference detection means always detects the interference applied to the two preset control channels, and the determination means determines which control channel is selected based on the detection signal. If the control channel that determines that there is less interference and the control channel that was determined to have less interference and the previously selected control channel are different, the control channel selection means selects only the control channel that the parent device control means determined to have less interference Control is performed again, and the determination result by the determination means is transmitted to the slave unit via the previously selected control channel. And in the child machine,
When the control signal receiving means receives the control channel,
The slave unit control means controls the control signal receiving means to intermittently receive only the control channel selected by the master unit based on the determination result included in the received control channel, so that the other electric power is automatically supplied. It is possible to always set a good control channel that is not affected by electromagnetic waves emitted from the product.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of a cordless telephone as an embodiment of the present invention, and FIG. 2 is a timing chart showing the intermittent reception timing of a cordless telephone in the cordless telephone.

In FIG. 1, 1 is a master unit connected to a telephone line 3, 2 is a slave unit connected to the master unit 1 through a plurality of channels, and 3 is connected to a partner's telephone through an exchange (not shown). It is a telephone line. Reference numeral 11 is a call circuit unit that is connected to the telephone line 3 and forms a call path between the partner telephone and the main telephone, 12 is a transmission circuit unit that performs signal processing such as modulation of a radio signal to the handset 2, and 13 is a child. A receiving circuit unit that performs signal processing such as demodulation of a radio signal from the device 2, and includes a detection unit 13a including a squelch circuit that detects the received electric field strength of the received signal received here. Reference numeral 14 is an antenna duplexer, 15 is an antenna for exchanging radio signals with the handset 2, and 16 is a communication circuit unit 11 and a transmission circuit unit 12.
And a modem connected to a signal path between the receiver circuit section 13 and an analog signal handled by the call path and a digital signal handled by the master unit control section 17, and 17 is input via the modem 16. A master unit control unit that controls each unit based on a control signal according to the control signal 18 is an operation button (manual operation unit) that arbitrarily drives a specific control of the master unit control unit 17.

Reference numeral 21 is an antenna for wireless communication with the master unit 1, 22 is an antenna duplexer, 23 is a transmission circuit section for performing signal processing such as modulation of radio signals to the master unit, and 24 is the master unit 1.
A receiving circuit unit that performs signal processing such as demodulation of a wireless signal from
25 is a microphone that collects voice signals sent to the other party's telephone,
Reference numeral 26 is a speaker that emits a voice signal from the other party's telephone, and 27 is an analog signal that is connected to the signal path between the transmission circuit unit 23 and the microphone 25 and the reception circuit unit 24 and the speaker 26, and is handled in the call path. And a modem for converting a digital signal handled by the slave unit control unit 28, 28 is a slave unit control unit for controlling each unit based on a control signal input via the modem 27, and 29 is an access to the partner telephone. The key input unit includes a numeric keypad for inputting a telephone number for performing the call, various mechanism keys, and the like.

Then, the communication circuit section 11 and the transmission circuit section 1
2, receiving circuit unit 13, antenna duplexer 14, antenna 1
5, the modem 16, the master unit control unit 17, and the operation buttons 18 configure the master unit 1, and the antenna 21, the antenna duplexer 22, the transmission circuit unit 23, the reception circuit unit 24, the microphone 2
5, the speaker 26, the modem 27, the cordless handset control unit 28, and the key input unit 29 constitute the cordless handset 2.

In the base unit 1, the transmission circuit section 12 constitutes a control signal transmitting means, and the base unit control section 17 constitutes a control channel selecting means, a call channel selecting means, a judging means and a base unit controlling means. Further, the detecting section 13a provided in the receiving circuit section 13 constitutes an interference detecting means. In addition, in the child device 2, the receiving circuit unit 2
4, the control signal receiving means is constituted, and the handset control section 28 constitutes a communication channel recognition means and a handset control means.

In the cordless telephone configured as described above, the slave unit 2 is driven by a secondary battery (not shown), and therefore the reception state of the control channel is constantly maintained in order to extend the maximum standby time of the slave unit 2 by the battery. Instead of holding, the control channel is received intermittently. Therefore, the timing of intermittent reception in the slave unit will be described based on the timing chart shown in FIG.

In FIG. 2, (a) shows the intermittent reception timing of the slave unit 2 when there are two control channels transmitted from the master unit 1, and (b) shows the control channel transmitted from the master unit 1. Represents the intermittent reception timing of the handset 2 when there is only one.

In FIG. 2A, for example, if the first control channel is held for a predetermined period of time at the time Ta, the first control channel and the second control channel until the next time Tb. Does not perform the receiving operation of
The second control channel different from the first control channel at time Tb
Control channel is held for a predetermined time in the reception operation, and thereafter, the reception operations of the first control channel and the second control channel are repeatedly held at intervals of time (Tb-Ta). That is, the first control channel is held for a predetermined time in the receiving operation at time Tc when time (Tb-Ta) has elapsed from time Tb. Then, in the child device 2, time Ta ~
Since the secondary battery is not used during the time when the receiving operation is not performed in Tb and Tb to Tc, it is possible to suppress the consumption of the secondary battery and to extend the maximum standby time of the slave unit 2 by the secondary battery. .

The longer the time during which the receiving operation is not performed in the times Ta to Tb, the longer the maximum standby time of the secondary unit 2 by the secondary battery can be extended, but the first control channel and the second The response to the base unit 1 by the control channel of 1 becomes slow. That is, for example, time Ta-
If the interval of Tb is 0.5 seconds, the interval of Ta to Tc is doubled to 1 second. Therefore, immediately after the holding of the receiving operation of the first control channel of Ta to Tb is released, the master device 1 is set to the first When the slave unit 2 is called by using the control channel of, the maximum reaction time in which the slave unit 2 reacts with the master unit 1 is about 1 second, and if the interval between Ta and Tb is set to 1 second, the maximum response time is 2 seconds. Although the maximum standby time of the handset 2 is extended by the secondary battery,
The maximum reaction time with respect to the master device 1 is about 2 seconds, and the reaction becomes poor.

On the other hand, in FIG. 2B, for example, time T
Assuming that the first control channel is held in the receiving operation for a predetermined time at the time point a ′, the first control channel is kept in the first time until the time point tb ′.
No receiving operation of the control channel is performed, the first control channel is again held for a predetermined time at the receiving operation at time Tb ', and thereafter, the first control channel is separated by an interval of time (Tb'-Ta'). The reception operation of is held repeatedly.
That is, the first control channel is held for a predetermined time in the receiving operation at the time Tc 'when the time (Tb'-Ta') has elapsed from the time Tb '. Since the secondary device does not use the secondary battery during the time when the receiving operation is not performed at the times Ta ′ to Tb ′ and Tb ′ to Tc ′,
The consumption of the secondary battery can be suppressed, and the maximum standby time of the secondary device 2 due to the secondary battery can be extended.

If, for example, the interval between the time Ta 'and Tb' is 0.5 seconds, the base unit 1 is set to the first unit immediately after the hold of the receiving operation of the first control channel Ta 'to Tb' is released. When the cordless handset 2 is called using the control channel of, the maximum reaction time for the cordless handset 2 to react with the cordless handset 1 is about 0.5 seconds, and the interval of Ta ′ to Tb ′ is 1 If the time is set to 2 seconds, the maximum standby time of the secondary device 2 by the secondary battery is extended and the maximum reaction time with respect to the primary device 1 is about 1 second, resulting in poor reaction, but compared to the one using two control channels. The reaction is not so bad.

Next, the control channel selection control operation in the cordless telephone in which the handset 2 is performing the intermittent reception as described above will be described.

When the control channel is not selected in the master unit 1 and the slave unit 2, the master unit 1 uses which of the two control channels to control the connection with the slave unit 2. May be, and the child device 2 is shown in FIG.
The intermittent reception is performed according to the timing shown in the timing chart.

When the control channel selecting operation is performed in this state, the reception frequency in the reception circuit section 13 of the master unit 1 is adjusted to the frequency where the first control channel is located, and the reception operation is started, and the detection section 13a. Detects the received electric field strength and the like from the received signal and detects the level of the signal located in this frequency band. Then, the modem 17 converts the detection signal into a signal that can be processed by the master controller 18, and the master controller 18 stores and holds the detection signal converted by the modem 17 as a first detection signal. Keep it.

Then, the reception frequency in the reception circuit unit 13 is adjusted to the frequency at which the second control channel is located to start the reception operation, and the detection unit 13a determines how much of the received signal from the received signal. It is detected whether the level signal is located in this frequency band. Then, similarly to the above operation, the master unit control unit 18 stores and holds the detection signal converted by the modem 17 as the second detection signal, and compares the first detection signal and the second detection signal stored and held last time. Then, which level is lower is determined. Then, the parent device control unit 18 determines that the control channel corresponding to the detection signal determined to have a low level is less likely to be affected by the electromagnetic waves emitted from other electric products, and thereafter, only the control channel is used for the control signal. Is transmitted to the slave unit 2, and a control signal is transmitted to the slave unit 2 through the selected control channel, and the master unit 1 thereafter controls this control channel as a control channel. Communicate using the channel.

Then, in the handset 2, the control signal transmitted through this control channel is received by the receiving circuit section 24 through the antenna 21 and the antenna sharing section 22, the control signal is extracted from the received signal, and the modem is used. 27
The slave unit control unit 28 converts the signal into a signal which can be processed by the slave unit control unit 28, and the slave unit control unit 28 recognizes the control channel used by the base unit 1 thereafter based on the control signal converted by the modem 27. The receiving circuit unit 24 is controlled so as to perform intermittent reception only on the control channel.

Along with this, the master unit 1 controls the connection with the slave unit 2 using the selected control channel,
The slave unit 2 intermittently receives the selected control channel at the timing shown in the timing chart of FIG. Therefore, since the slave unit 2 performs the intermittent reception of one control channel at the timing shown in the timing chart of FIG. 2A, the slave unit using the secondary battery does not deteriorate the maximum reaction time for the master unit 1. The maximum standby time of 2 can be extended.

Next, the control channel selection control operation in the base unit 1 will be briefly described with reference to the flowchart shown in FIG.

In step F1, it is judged whether or not the control channel is selected in the master unit 1, and if it is judged that the control channel is selected, it is judged that the control channel is not selected. If this operation is repeated and it is determined that the control channel has not been selected, the process proceeds to step F2.

In step F2, the reception frequency in the reception circuit section 13 is set to the frequency f at which the first control channel is located.
_In step F3, the noise level is detected from the signal received at the reception frequency f ₁ set by the receiving circuit unit 13 and stored as the first detection signal K ₁ in step F3. Move to. In step F4, the reception frequency in the reception circuit unit 13 is adjusted to the frequency f ₂ at which the second control channel is located, and the process proceeds to step F5. In F5, the reception frequency f ₂ set in the reception circuit unit 13 is received. The noise level is detected from the signal and stored as the second detection signal K ₂ , and the process proceeds to step F6.

In step F6, it is judged whether or not the detection signal K ₁ detected and stored in step F3 is smaller than or equal to the detection signal K ₂ detected and stored in step F5, and the detection signal K ₁ is detected. If it is determined that it is smaller than or equal to K ₂ , the process proceeds to step F7, and if it is determined that the detection signal K ₁ is not greater than the detection signal K ₂ , the process proceeds to step F8.

In step F7, only the first frequency f ₁ is selected as the transmission frequency of the control signal in the transmission circuit section 12, only the first control channel is used as the control channel, and the process proceeds to step F9. In step F9, the control signal notifying that only the first control channel will be used thereafter is transmitted using the first frequency f ₁ selected in step F7, and this flowchart ends.

On the other hand, when the process moves from step F6 to step F8, in step F8, only the second frequency f ₂ is selected as the transmission frequency of the control signal in the transmission circuit section 12, and the second control channel is selected as the control channel. Only the second control channel is used by using the second frequency f ₂ selected in step F8. The flowchart ends.

The control channel selecting operation of the slave unit 2 with respect to the control channel selecting operation of the master unit 1 will be described with reference to FIG.
A brief description will be given based on the flowchart shown in FIG.

In step F11, it is judged whether or not the control channel is selected in the handset 2, and when it is judged that the control channel is selected, it is judged that the control channel is not selected. If this operation is repeated and it is determined that the control channel has not been selected, the process proceeds to step F12.

[0042] and intermittently reception operation in alternating first frequency f ₁ and the first control channel is located a second frequency f ₂ in which the second control channel is located in the receiving circuit section 24 in step F12 Perform step F13
Then, in step F13, it is determined whether or not the control signal from the master device 1 is received by the intermittent reception operation of the first control channel and the second control channel in step F12, and the control signal is received. If it is determined that the control signal has not been received, the procedure is repeated until the control signal is received. If it is determined that the control signal is received, the procedure proceeds to step F14.

In step F14, it is determined whether the control signal is received on the first control channel or the second control channel. If it is determined that the control signal is received on the first control channel, step F14 is performed. Move to F15,
When it is determined that the control signal is received on the second control channel, the process proceeds to step F16.

In step F15, information regarding the selection of the control channel is read from the received control signal, and the control channel selected in the parent device 1 is recognized as the first control channel based on the information, and the step F1 is performed.
In step F17, only the first frequency f ₁ is intermittently received as the reception frequency of the control signal in the reception circuit section 24, and the first control channel is used.
This flow chart is ended by using only the control channel of.

On the other hand, from step F14 to step F16
In the case of shifting to step F16, in step F16, information regarding the selection of the control channel is read from the received control signal,
The control channel selected by the parent device 1 based on the information is recognized as the second control channel, and the process proceeds to step F18. At step F18, the second frequency f is set as the reception frequency of the control signal in the reception circuit unit 24. This flow chart is terminated by receiving only ₁ intermittently and using only the second control channel as the control channel.

Therefore, the connection control with the slave unit 2 can be performed by the control channel selected in the master unit 1.
Since the intermittent reception is performed using only one control channel, the maximum standby time of the secondary device 2 by the secondary battery can be extended without deteriorating the maximum reaction time for the primary device 1.

Next, the control for arbitrarily performing the control channel selection control operation by operating the operation button 18 of the base unit 1 will be briefly described with reference to the flowchart shown in FIG. Note that, in FIG. 5, parts common to those in FIG. 3 are denoted by common reference numerals.

In step F21, it is determined whether or not the operation button 18 is pressed, and this operation is repeated until it is determined that the operation button 18 is pressed. When it is determined that the operation button 18 is pressed, the process proceeds to step F22. . In step F22, the selection by the transmission circuit unit 12 is canceled, and the process proceeds to step F1. Thereafter, the control channel selecting operation is performed.

Then, step F9 or step F10
In step S6, the control signal for notifying that only the first control channel or the second control channel reselected in step F7 or step F8 is used by using the frequency previously selected is transmitted, and this flowchart is ended.

The control channel selection control operation of the child device 2 with respect to the control channel selection control operation of the parent device 1 is the same as step F14 and subsequent steps of the flowchart shown in FIG.

Therefore, after selecting the control channel used to control the connection between the master unit 1 and the slave unit 2, noise is generated in the control channel and the call connection between the master unit 1 and the slave unit 2 can be established. Even if it disappears, a good control channel can be set again by arbitrarily selecting the control channel again.

The selection control operation for automatically selecting a good control channel in the master unit 1 will be briefly described with reference to the flowchart shown in FIG. In FIG. 6, parts common to those in FIGS. 3 and 4 are designated by common reference numerals.

After the first control channel or the second control channel is selected based on the operation of step F1 to step F9 or step F10, step F31
Then, in step F31, it is determined whether or not the control channel selection control operation is automatically performed to always select the good control channel. For example, based on the preset mode, the always good control channel is selected. If it is determined that the control channel selection control operation is not performed automatically, the process proceeds to step 32. If it is determined that the control channel selection control operation is not automatically performed, only the control channel selected in step F7 or step F8 is used for the subsequent parent operation. The connection between the device 1 and the child device 2 is controlled, and this flowchart ends.

On the other hand, in step F32, it is determined whether or not a predetermined time has elapsed, and this operation is repeated until it is determined that the predetermined time has elapsed. When it is determined that the predetermined time has elapsed, the process proceeds to step F2, Repeat the operation.

When switching the control channel to be selected in the repetition of the above operation, the slave channel 2 is selected by the same operation as when the control channel selection control operation is arbitrarily performed by operating the operation button 18 described above. The control channel selection control channel of the previous unit is used when transmitting the control signal including the information of the above, and the control channel selection control operation of the slave unit 2 with respect to the control channel selection control operation of the parent unit 1 is step F1 of the flowchart shown in FIG.
It is the same as 4 or later.

Therefore, after the control channel used for controlling the connection between the master unit 1 and the slave unit 2 is selected, if it is determined that the other control channel is better than the control channel, the control channel is automatically changed. It is possible to select a control channel that is determined to be good, and always set a good control channel again.

In this embodiment, the operation button 18 as the manual operation means is provided on the base unit 1 side, but the present invention is not limited to this, and for example, the key input unit 2 provided on the handset unit 2.
9 may be set as a manual operation means, and a control signal corresponding to the operation may be transmitted to the master unit 1 side.

[0058]

As described above, according to the first aspect of the present invention, the interference detecting means in the master unit detects the interference on the two preset control channels and makes a determination based on the detection signals. Means determines which control channel has less interference, and the master unit control means controls so that the control channel selection means selects only the control channel determined to have less interference, and the determination result by the determination means To the child device. When the control signal receiving means receives the control channel in the child device,
When the slave unit is on standby by controlling the slave unit control unit so that the control signal receiving unit intermittently receives only the control channel selected by the master unit based on the determination result included in the received control channel. For the call connection between the master unit and the slave unit in, the control channel that is not affected by the electromagnetic waves emitted from other electric products is selected in advance, and since it is performed by that one control channel, the control channel selected by the master unit is used. Since the connection control with the slave unit can be performed and the intermittent reception is performed using only one control channel, the maximum standby time of the slave unit by the secondary battery can be achieved without deteriorating the maximum reaction time for the master unit. Can be extended.

According to the second aspect of the invention, in response to the operation by the manual operation means, the master unit control means temporarily cancels the selection of the control channel of the control channel selection means, and the interference detection means is accompanied by the cancellation. While detecting the interference on the two preset control channels, the determination means determines which control channel has less interference based on the detection signal, and the master device control means determines that the interference is less. Only the control channel is controlled again by the control channel selection means, and the determination result by the determination means is transmitted to the slave unit via the previously selected control channel. Then, in the slave, when the control signal receiving means receives the control channel, the slave signal controlling means causes the control signal receiving means to select only the control channel selected by the master based on the determination result included in the received control channel. By controlling to receive signals intermittently, it is possible to reconfigure a good control channel that is not affected by the electromagnetic waves emitted from other electronic products by the user's operation, so the connection between the master unit and the slave unit After selecting a control channel to be used for control, even if noise occurs on that control channel and the call connection between the master and slave cannot be established, the control channel selection control can be performed again. Can reset a good control channel.

According to the third aspect of the present invention, the interference detection means always detects the interference applied to the two preset control channels, and the determination means determines which control channel is more interfered based on the detection signal. If the control channel determined to have less interference is different from the previously selected control channel, the master channel control means selects only the control channel determined to have less interference. Then, the determination result by the determination means is transmitted to the slave unit through the previously selected control channel. Then, in the slave, when the control signal receiving means receives the control channel, the slave signal controlling means causes the control signal receiving means to select only the control channel selected by the master based on the determination result included in the received control channel. By controlling to receive intermittently, it is possible to automatically set a good control channel that is not affected by electromagnetic waves emitted from other electronic products at all times, making it possible to control the connection between the master unit and the slave unit. After selecting the control channel to be used, if the other control channel is judged to be better than that control channel, it can be automatically selected as the control channel judged to be good, and always It can be set back to a good control channel.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a cordless telephone that is an embodiment of the present invention.

FIG. 2 is a timing chart showing the timing of intermittent reception of a handset in the cordless telephone.

FIG. 3 is a flowchart showing a control channel selection control operation of the master unit in the cordless telephone.

FIG. 4 is a flowchart showing a control channel selection control operation of a handset in the cordless telephone.

FIG. 5 is a flowchart showing a control channel selection control operation by a manual operation in the cordless telephone.

FIG. 6 is a flowchart showing a control channel automatic selection control operation in the cordless telephone.

[Explanation of symbols]

 1 master unit 2 slave unit 11 call circuit unit 12, 23 transmission circuit unit 13, 24 reception circuit unit 14, 22 antenna duplexer 15, 21 antenna 16, 27 modem 17 master unit control unit 18 operation button 25 microphone 26 speaker 28 child Machine control unit

Claims (3)

[Claims] 1. A master unit connected to a telephone line and a slave unit connected to the master unit by a plurality of wireless channels, wherein the master unit is a slave unit from two preset control channels. Control channel selecting means for selecting a control channel used for connection control of the communication channel, a communication channel selecting means for selecting an empty channel from a plurality of wireless channels, and data relating to the empty channel selected by the communication channel selecting means. Control signal transmitting means for transmitting via the control channel selected by the channel selecting means, while the slave unit intermittently receives two control channels preset in the master unit. And an empty channel included in the control channel received by the control signal receiving means. And a call channel recognition means for recognizing a call channel used for a call with the base unit based on the data stored in the base unit, and the call connection between the base unit and the base unit during standby of the handset is performed by the base unit. In a cordless telephone that receives data relating to an empty channel selected by the device via a control channel, the master device includes an interference detection means for detecting an interference on each of two preset control channels. The control channel selecting means determines only the control channel determined by the determining means based on the detection signal from the interference detecting means to determine which control channel has less interference. A master unit that controls to select and transmits the determination result by the determination unit via the control channel The control signal receiving means intermittently receives only the control channel selected by the parent device on the basis of the determination result included in the control channel received by the control signal receiving means, in the slave device. A cordless telephone characterized in that a cordless handset control means for controlling the above is provided. 2. A manual operation unit for arbitrarily controlling the control channel selection unit by the master unit control unit is provided, and the master unit control unit selects the control channel in response to an operation by the manual operation unit. The previously selected state by the means is once released, and control is performed so that the channel selection means selects only the control channel which is determined to be less disturbed by the determination means again, and the determination result by the determination means is selected last time. The cordless telephone according to claim 1, wherein the cordless telephone is transmitted via a control channel. 3. The interference detection means and the determination means always detect the interference applied to two preset control channels and determine which control channel has less interference, while the master device control means. When the control channel determined to be less disturbed by the disturbance detecting means and the determining means is different from the previously selected control channel, the channel selecting means selects only the control channel determined to be less disturbing by the determining means. 2. The cordless telephone according to claim 1, wherein the cordless telephone is controlled as described above, and the judgment result of the judgment means is transmitted via the previously selected control channel.